This week in Across Africa: Central African Republic's government signs a peace deal with over a dozen militia groups. It's the eighth such agreement since fighting began in 2013. Also, bosses behind a mammoth Ponzi scheme in Benin are jailed for 10 years after defrauding more than 150,000 people, many of whom lost everything. And Kenyan fishermen around Lake Victoria struggle to make it out to open water because of the persistent invasion of water hyacinth.